The Dresden Files by Jim Butcher is suitable for readers aged 12 and up. The series follows the adventures of the titular character, Harry Dresden – a professional wizard detective in modern day Chicago. The books contain appealing characters, life-or-death struggles and complex storylines, which make it attractive to readers of all ages.
However, due to the presence of supernatural elements and some mature content, it is best enjoyed by mature readers. There is violence, language, and some suggestive behaviour, although it is never gratuitous. For example, there are one or two scenes containing sexual remarks, but not to an extreme degree.
Overall, The Dresden Files can be enjoyed by teens, young adults and adults. It is an imaginative, exciting and engaging series that is sure to captivate readers of all ages.
If you have any further questions about the suitability of this series for any particular age group, don't hesitate to contact your local library or public bookstore. They will be able to provide more detailed information.
Good luck, and enjoy your journey into The Dresden Files!